Humification process enhancement through relative abundance promotion of Talaromyces and Coprinopsis by inoculated Phanerochaete chrysosporium during the secondary fermentation of composting

To explore the mechanism of Phanerochaete chrysosporium (P. chrysosporium) inoculation driving the humification process of maize straw composting, the treatments without P. chrysosporium inoculation (T1) and that with P. chrysosporium inoculation (T2) were carried out separately during the secondary fermentation of the co-composting of maize straw and rapeseed cake. The key microorganisms were determined by evaluating the succession of the fungal community and its relationship with humification process parameters. The results showed that P. chrysosporium inoculation (T2) reduced fungal diversity but increased the relative abundance of Coprinopsis and Talaromyces. At the end of the composting (day 36), the relative abundance of Talaromyces and Coprinopsis in T2 increased by 1223.7% and 30.2%, respectively, compared with T1. Combined CCA and SEMs analyses demonstrated the microbially driven mechanisms that enhance the humification process of composting, that is, P. chrysosporium inoculation promoted lignin continuous degradation by promoting the relative abundance of Talaromyces and Coprinopsis during the secondary fermentation of composting; meanwhile, P. Chrysosporium inoculation further intensified the biological process of humification in composting.